Blogs

About this blog

I'm a well-known mainframe performance guy, with almost 30 years of experience helping customers manage systems. I also dabble in lots of other technology. I've sought to widen the Performance role, incorporating aspects of infrastructural architecture.
I'm a world-famous podcaster and screencaster (albeit VERY thinly spread). :-)

Tags

Recent tweets

Find us on Facebook

It's been a while since I last posted here. And that's been more a matter of being incredibly busy than anything. Some of you will have seen me "on stage" - there having been several conferences and user groups recently. Some of you were with me at the zChampions meeting and some of you I'm actively working on customer situations with. (By the way one of the rules of zChampions isn't... [More]

In the distant past I've written about using DFSORT to parse XML. This post (and two follow-on posts) will describe
an experiment to make such processing much more robust. In this post I'll talk about what the problem I'm trying to solve is. And why. And a brief outline of my solution. About XML This isn't meant to be the most detailed description of XML, nor a complete list of where it's used. I... [More]

Many of you will have, by now, installed the Adobe AIR runtime. Most probably it will be to run something like Twhirl. At this point many of you will be asking "what's Twhirl?" If I said it was a nice desktop application that makes using Twitter so much easier I hope you don't ask "what's Twitter?" :-) So, we're beginning to see these desktop applications coded using Adobe AIR, which stands for... [More]

This is the second part of a (currently) three-part series on processing XML data with DFSORT, given a little help from standard XML processing tools. The first part - which you should read before reading on - is here . To recap, getting XML data into DFSORT is a two stage process: Flatten the XML data so that it consists of records with fields in sensible places. Process this flattened data with... [More]

Frank Yaeger of DFSORT Development suggested I pass this tip along to y'all. It's his solution to a problem set by Brian Peterson of UnitedHealth Group... In z/OS Release 12 two new messages were introduced: IEF032I and IEF033I replace IEF374I and IEF376I. The older messages were single-line step- and job-end messages. The new ones are their multiple-line analogues: IEF032I is 3 lines and... [More]

It's going to sound like the only thing I talk about is DFSORT. While that isn't entirely true I am currently updating my "What's New With DFSORT?" foils. And it made me think about processing SMF data... In our internal analysis processes we chuck SMF data around quite a bit, whether subsetting it or actually mangling the records. In this entry I want to talk about subsetting - as most people... [More]

As many of you know I've been very fond of BatchPipes/MVS (aka "Pipes") down the years (17 to be precise). So I'm pleased to see APAR PK34251: ADDING BATCHPIPES SUBSYS SUPPORT TO TEMPLATE UTILITY describes some new support in the DB2 Load Utility (as driven by the Template utility) which makes it much easier to use with BatchPipes/MVS. (For reference here's the BatchPipes For OS/390 Version 2... [More]

You'd think it would be pretty simple to draw a line. Right? This post discusses an enhancement I'd like to make to my current reporting - and I'm pretty sure that technically I can do it. The question is whether I should . Consider my current "Memory by address space within Service Class" graph. Here's a sample: And here's what I think I might like it to look like: Obviously the line's... [More]

I've just re-read the XCF (74-2) and CF (74-4) sections of the z/OS Release 9 SMF Manual. There are some nice things in there... XCF (74-2) Number of buffer 1KB blocks by path (R742PUSE). This should tell you whether memory waste by over-specifying CLASSLEN is a problem. And some of the other scenarios. Member job name (R742MJOB). I'd like to believe this would tell us which IRLM a given member... [More]

About a year ago I posted: A Small Step For RMF, A Giant Leap For Self-Documenting Systems . A year on I've encountered some customer data that's made me go "huh?", related to this. In the referenced post I mentioned R744FLPN, the Coupling Facility's LPAR Number. For the first time I've seen data where the match - with SMF 70 Logical Partition Number (in Logical Partition Section) -... [More]

Back in z/OS R.9 RMF Parallel Sysplex New Fields (in 2007) I mentioned a new field: R742MJOB (XCF Member Job Name.) At the time I had no real customer data so I could only espouse the HOPE that this field would be useful. (When I asked for it to be added to the SMF 74 Subtype 2 record it seemed to me it probably would be.) Now that z/OS R.9 is "mainstream" I'm seeing lots of data at this level.... [More]

It's nice to see a flurry of activity in IBM-MAIN about Hiperbatch. And it's more for the emotional reason of reminiscence than for any stunning insights that I'm blogging about it... Back in 1988 I ran a technical project in my then customer, Lloyds Bank, to evaluate Data In Memory (DIM). It was a fun project with a wide range of workloads on multiple machines, including the then-new DB2. So we... [More]

As previously discussed I'm often in a situation of trying to make sense of a set of job-related SMF data. Even though it may be your own installation's data, you're probably confronted with what I like to call “a journey of discovery” occasionally, too. I'm always looking for what I can discern from the data. 1 And, when confronted with a set of data about batch jobs, I go into overdrive. This... [More]

I can't believe it's been almost a week since I wrote Batch Capacity Planning, Part 1 - CPU . Where did the time go? Re-reading it I'm struck by the overwhelming theme of Batch's unpredictability and lumpiness. This is true of memory, as well, but to a much lesser degree. Why to a lesser degree? Well, in most systems I look at the memory usage is mostly fairly constant and dominated by big... [More]

If you think this title is obscure bear in mind the original working title was "Send In The Hobgoblins". 1 When I started to write - actually before the "mind mapping" stage - it was going to be all about inconsistency in the way bits of systems are named. You'll see some of that reflected in the finished article (pun intended) but the post has mostly gone in a different... [More]